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This paper presents our latest results from the investigation of the surface oxide content in boron capped layers used as the entrance window in ultraviolet silicon (UV-Si) photodetectors. These photodetectors have been studied electrically and optically to define the correlation between oxide content and performance, i.e. The direct relationship between the amount of undesired surface oxide in the active region where the boron layer is deposited, and the detector stability to high UV exposure levels. The boron capping layers were deposited by either chemical or physical vapor based deposition techniques (CVD or PVD). Although these techniques provide photodetectors that are highly sensitive to UV radiation [1], the formation of surface oxide during deposition is a major concern, especially for stability. To analyze the oxide content, an XPS (X-ray photoelectron spectroscopy) analysis was performed on high-temperature (HT-CVD: 700 °C), low-temperature (LT-CVD: 400 °C), and room-temperature (RT-CVD: 25 °C) based pure boron (PureB) photodetectors. An inverse relationship between deposition temperature and oxide content was noticed. While the HT-CVD based photodetectors were found to contain 30% of oxide in its active region, this amount drops to less than 10% for LT-CVD, and to a few percent for RT-PVD based process.

The capability of Si-based PureB photodetectors to withstand UV radiation is an unconditional requirement for a variety of industrial applications. A good example can be found in the next-generation 13.5-nm lithography systems [1]: UV detectors used to optimize the imaging performance will be exposed to EUV radiation levels as high as a few mJ/cm2 [2]. It has been demonstrated in [3] that only 2-nm thick pure boron layer can be resistant to detrimental environments. Such boron layer can be added to fully processed BSI/FSI CMOS imagers as end-of-line capping layer, to passivate their surface, as well as to increase the spectral range of their sensitivity from IR down to soft x-ray. In both applications negligible degradation of the electrical and optical behavior of the photodiodes/devices is highly demanded.

Free radicals scavenging and advanced glycation end-products (AGEs) inhibitory potentials in crude chloroform extract of Schisandra grandiflora were evaluated. Bioassay-guided isolation of the chloroform extract led to the identification of 24 compounds. Among the isolates, ( ± ) gomisin M1, arisantetralone C and D, macelignan, saurulignan B and SZ-MO displayed potent-free radical scavenging as well as AGEs inhibitory potentials. This is the first report identifying the presence of AGEs inhibitory activity and assigning AGEs inhibitory activity to these compounds. Therefore, our research finds new application of traditional medicinal plant S. grandiflora having capacity to reduce formation and accumulation of AGEs in diabetes.

This paper describes a study of the mechanical properties of as-cast and heat-treated ZA-27 zinc-aluminium alloy particulate composites containing silicon carbide (SiC) particles of size 100–150 μm and of contents ranging from 0% to 5% by weight. The ‘vortex method’ of production was employed in which the SiC particles were poured into the vortex created by stirring the molten metal by means of a mechanical agitator. Subsequent homogenizing heat treatment was performed at 320°C for durations of 1, 2, 3 and 4 hours, respectively. The results of this study revealed that as SiC composition was increased, there were significant increases in the ultimate tensile strenght (UTS) and hardness of the composite, accompanied by reductions in its ductility and impact strength. Heat treatment was found to improve significantly the ductility and impact strength of the composite, but cause reductions in its UTS and hardness. An attempt is made in the paper to provide explanations for these phenomena.

Design and optimization of backside-thinned CMOS active pixel sensors (APS) using modeling and simulation is presented. For the efficient design and the further improvement of our backside-thinned CMOS imagers, different models were developed and TCAD simulating tools were used. The imagers have been successfully designed, fabricated and tested and proved to possess excellent imaging properties. This short abstract paper presents a summary of the models and simulations covering two critical design and processing issues, namely the epilayer (EPI) structure and the pixel isolating trench formation process as well as their influence on the electrical inter-pixel crosstalk.

The subspace clustering algorithm CLIQUE finds all subspace clusters including overlapping clusters existing in high dimensional datasets. CLIQUE consists of three main steps namely - (1) identification of subspaces that contain clusters, (2) identification of clusters and (3) generation of the minimal description for the clusters obtained in step two. In this paper, we have presented a method for speeding-up the first step of the CLIQUE algorithm. The proposed method is based on accessing the data from columns instead of rows. It is very efficient when there are many missing values in the high dimensional datasets given in the form of table. We have also proposed a depth-first method to find the maximal dense units, to further improve the performance of the first step

Summary form only given. A four-stage axisymmetric depressed collector was successfully designed and developed to recover nearly 80% of the spent beam kinetic energy for a high efficiency C-band 60 W space TWT. The PIERCE program [LK-MTRDC] was used to optimize shape, size and operating depressed voltage of each electrode of the 4-stage depressed collector for achieving optimum energy recovery from the spent electron beam with minimum loss of collector efficiency caused by secondary electrons from back streaming. The program uses geometrical parameters of the electrodes and the spent beam trajectories data. The electron beam trajectories data were generated from the SUNRAY-3D large-signal model [VS-CEERI] and SUNBRS program [VS-CEERI] for the TWT operating at saturation output power at centre frequency 3.90 GHz. The SUNBRS code was used for analyzing the spent beam passing through the beam refocusing section (BRS) which was used before the collector for improving its performance. Radial velocities in the spent beam were reduced by decreasing PPM focusing magnetic field along the BRS.

Although the full radix-4 CORDIC algorithm is efficient compared to the standard radix-2 version, the scale-factor overhead causes its improvement to be limited. In this work, an algorithm and its associated architecture have been proposed for parallel compensation of the scale factor for the radix-4 CORDIC algorithm in the rotation mode. The proposed method, which makes no prior assumptions about the elementary angles of rotation, reduces the latency from n to (n/2)+3, where n is the precision length in bits, at the cost of a reasonable increase in hardware complexity. The architecture presented relates to the redundant signed-digit number system. The architecture has been modelled in VHDL and simulated to establish its functional validity.

The noble-metal tetrafluorides IrF4, RhF4 and PdF4 have been synthesized. All three fluorides are isostructural with PtF4 the unit cells being face centred orthorhombic, Z = 8, (probable space Fdd2) with the following parameters: a 0 ( A ) b 0 ( A ) c 0 ( A ) V( A 3 ) IrF 4 9·64(2) 9·25(2) 5·67(1) 505·8 RhF 4 9·71(2) 9·05(2) 5·63(1) 494·7 PdF 4 9·37(2) 9·24(2) 5·84(1) 505·6 PdF4 is diamagnetic (low spin d6) whereas RhF4 and IrF4 are paramagnetic. The magnetic susceptibility of the latter obeys a Curie-Weiss law over the temperature range 100–300°K (θ = − 60°K) with μeff = 1·89 B.M.. Below 100°K significant deviation from the Curie-Weiss relationship occurs. This and the large negative value of the Weiss temperature are consistent with antiferromagnetic coupling between adjacent iridium atoms. This is in harmony with a proposed structural model.

Six endogamous Brahmin subsects, viz., Niyogi, Madwa, Dravida, Vadahalai, Tengalai and Vaidiki of Andhra Pradesh (A.P.), India, were investigated for genetic differentiation using biochemical genetic markers. One of the subsects, Vaidiki, was also investigated in three different locations to study genetic variation between themselves resulting from geographic isolation. The values obtained for eight polymorphic loci were used and B 2 values ( Balakrishnan & Sanghvi, 1968 ) were obtained. A dendrogram was drawn by the fusion method of binary split (Balakrishnan et al. , 1975). Using the first three principal co-ordinates of the centroid adjusted similarity matrix ( Gower, 1966 ) a three-dimensional representatation was given to the genetic distances.

Measurements of the dimensions and membrane rotational frequency of individual erythrocytes steadily tank-treading in a rheoscope are used to deduce the surface shear viscosity of the membrane. The method is based on an integral energy principle which says that the power supplied to the tank-treading cell by the suspending fluid is equal to the rate at which energy is dissipated by viscous action in the membrane and cytoplasm. The integrals involved are formulated with the aid of an idealized mathematical model of the tank-treading red blood cell (RBC) (Keller and Skalak, 1982, J. Fluid Mech., 120:24–27) and evaluated numerically. The outcome is a surface-averaged value of membrane viscosity which is representative of a finite interval of membrane shear rate. The numerical values computed show a clear shear-thinning characteristic as well as a significant augmentation of viscosity with cell age and tend toward agreement with those determined for the rapid phase of shape recovery in micropipettes (Chien, S., K.-L. P. Sung, R. Skalak, S. Usami, and A. Tozeren, 1978, Biophys. J., 24:463–487). The computations also indicate that the rate of energy dissipation in the membrane is always substantially greater than that in the cytoplasm.

The theory of fixed point is a very extensive field, which has various applications. The present paper deals with some developments of Meir-Keeler type fixed point theorem as its remarkable generalizations under several contractive definitions in metric space.Key words: Common fixed point; Contraction; Metric space; Compatible mapsDOI: 10.3126/njst.v10i0.2956Nepal Journal of Science and Technology Vol. 10, 2009 Page: 141-147

A dielectric response approach to the Van der Waals interaction between an atom and a planar metal surface is presented. An exact formula in terms of a form factor is derived within the point dipole approximation and non-retarded limit valid for shorter separation. The interaction potential is studied via SCIB model, and a substantial modification over its classical form is found at shorter distances.

The distribution of the C5 isozyme of the serum cholinesterase (E2 locus) was studied in several endogamous Hindu caste groups and Muslim sub-sects of Andhra Pradesh in South India. Both intra and inter population variation was marked with a comparatively low incidence of C5 in the populations studied.

The peel of Citrus jambhiri lush., a lemon, from Nagaland and from the Assam plains contains both hesperidin and tangeretin. In addition, the plains variety contains neohesperidin. The phenolic compound obtained from the Nagaland variety has been assigned the structure of 5-O-desmethyltangeretin while a phenolic compound isolated from the plains variety has not been investigated

Presented is an algorithm for the approximate calculation of the membrane stress distribution and the internal pressure of a steadily tank-treading red cell. The algorithm is based on an idealized ellipsoidal model of the tank-treading cell (Keller, S.R., and R. Skalak, 1982, J. Fluid Mech., 120:27–47) joined with experimental observations of projected length, width, and tank-treading frequency. The results are inexact because the membrane shape and velocity are assumed a priori, rather than being determined via appropriate material constitutive relations for the membrane; these results are, nevertheless, believed to be approximately correct, and show that internal pressure builds up slowly as cell elongation increases, rising more rapidly as the deformed cell approaches the limiting geometry of a prolate ellipsoid. The maximum shear stress resultant in the membrane was found to be below but approaching the yield point range at the highest shear rate applied.

The stamina building, antistress and antihyperlipidemic principle of Cicer arietinum has been isolated and identified for the first time to be pangamic acid ( d -gluconodimethylaminoacetic acid) by chemical and spectral methods.